Method and device for scheduling request in NB IoT systems

ABSTRACT

A method and device for reporting scheduling request are provided. The method includes the operations of acquiring a dedicated physical resource of a random access channel (RACH) configured to report a scheduling request, when the scheduling request is triggered, transmitting the RACH on the dedicated physical resource. The dedicated physical resource includes a plurality of periodic physical resources. Through this dedicated physical resource, the user equipment (UE) can report scheduling request in a contention-free random access way, and the capacity of a preamble sequence is improved and inter-cell interference is reduced.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation application of prior application Ser.No. 15/926,321, filed on Mar. 20, 2018, which was based on and claimedpriority under 35 U.S.C. § 119(a) of Chinese Patent Application No.201710184821.9, filed on Mar. 24, 2017, in the Chinese Patent Office, ofChinese Patent Application No. 201710282236.2, filed on Apr. 26, 2017,in the Chinese Patent Office, and of Chinese Patent Application No.201710432231.3, filed on Jun. 9, 2017, in the Chinese Patent office, thedisclosure of each of which is incorporated by reference herein in itsentirety.

TECHNICAL FIELD

The disclosure relates to the technical field of narrowband (NB)internet of things (IoT). More particularly, the disclosure relates to amethod and device for reporting a scheduling request in NB IoT systems.

BACKGROUND

To meet the demand for wireless data traffic having increased sincedeployment of 4th-generation (4G) communication systems, efforts havebeen made to develop an improved 5th-generation (5G) or pre-5Gcommunication system. Therefore, the 5G or pre-5G communication systemis also called a ‘beyond 4G network’ or a ‘post long term evolution(LTE) system’.

The 5G communication system is considered to be implemented in higherfrequency millimeter wave (mmWave) bands, e.g., 60 GHz bands, so as toaccomplish higher data rates. To decrease propagation loss of the radiowaves and increase the transmission distance, the beamforming, massivemultiple-input multiple-output (MIMO), full dimensional MIMO (FD-MIMO),array antenna, an analog beam forming, large scale antenna techniquesare discussed in 5G communication systems.

In addition, in 5G communication systems, development for system networkimprovement is under way based on advanced small cells, cloud radioaccess networks (RANs), ultra-dense networks, device-to-device (D2D)communication, wireless backhaul, moving network, cooperativecommunication, coordinated multi-points (CoMP), reception-endinterference cancellation and the like.

In the 5G system, hybrid frequency shift keying (FSK) and quadratureamplitude modulation (QAM) modulation (FQAM) and sliding windowsuperposition coding (SWSC) as an advanced coding modulation (ACM), andfilter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA),and sparse code multiple access (SCMA) as an advanced access technologyhave been developed.

Narrowband internet of things (NB IoT) technology defines wirelessaccess of a cellular internet of things, which is greatly based on anon-backward compatible electric-universal telecommunication radioaccess (E-UTRA), enhances an extreme cover scene, and supports a hugeamount of low-speed internet of things user equipment (UEs), low-delaysensitivity, ultra-low cost and power devices, and optimized networksystem architectures.

The above information is presented as background information only toassist with an understanding of the disclosure. No determination hasbeen made, and no assertion is made, as to whether any of the abovemight be applicable as prior art with regard to the disclosure.

SUMMARY

Aspects of the disclosure are to address at least the above-mentionedproblems and/or disadvantages and to provide at least the advantagesdescribed below. Accordingly, an aspect of the disclosure is to providea method and device for reporting scheduling request in narrowband (NB)internet of things (IoT) systems, to solve at least one of the problemof excessive low use efficiency of system resources in the current NBIoT transmission scheduling request technology, and the problem ofinsufficient capacity of narrowband physical random access channel(NPRACH).

In accordance with an aspect of the disclosure, a method for reportingscheduling request in NB IoT systems is provided. The method includesacquiring a dedicated physical resource of an NPRACH used for schedulingrequest and, when the scheduling request is triggered, transmitting theRACH on the dedicated physical resource for reporting the schedulingrequest, wherein the dedicated physical resource comprises a pluralityof periodic physical resources.

In one embodiment, the dedicated physical resource comprises a timeresource, a frequency resource and a sequence resource.

In one embodiment, the time resource and frequency resource are acquiredaccording to a first system rule, or are configured by an evolved Node B(eNB).

The operation of being configured by the eNB comprises indicating, bythe eNB, a subcarrier index and/or a subframe index and/or repetitionnumber for reporting scheduling request, the first system rule comprisestransmitting, by using the subcarrier used in an initial access, anNPRACH as a scheduling request, or, by the first system rule,determining, according to the user equipment (UE) identity, atime-and-frequency resource, a time resource or a frequency resource,and, the time-and-frequency resource comprises a subcarrier and subframefor transmitting an NPRACH, the time resource comprises the subframe fortransmitting an NPRACH, and the frequency resource comprises asubcarrier for transmitting an NPRACH.

In one embodiment, the sequence resource comprises a preamble sequence,by the UE, acquiring, according to a preamble sequence acquisition rule,configuration information of the preamble sequence, the preamblesequence acquisition rule comprises at least one of a first rule that aunique preamble sequence is acquired or a second rule that the preamblesequence is determined according to a cell identity.

In one embodiment, the sequence resource comprises multiple preamblesequences, the length of the preamble sequence is M_(rep), where M_(rep)is the submultiple of the number of the total NPRACH repetitions, andthe generation rule of the preamble sequence is within each repetitionof the NPRACH, one same element of the preamble sequence is transmittedby each symbol, and elements of preamble sequence is transmitted insequence by every M_(rep) repetitions of the NPRACH, or, if the lengthof the preamble sequence is the same as the number of the symbol groupsof NPRACH, the generation rule of the preamble sequence is one elementof the preamble sequence is transmitted repeatedly by all the symbolswithin one symbol group of the NPRACH, and each element of the preamblesequence is transmitted in sequence according to a sequence of symbolgroups, or, if the length of the preamble sequence is the same as thetotal number of symbols of M_(rep) repetitions of the NPRACH, thegeneration rule of the preamble sequence is during M_(rep) repetitions,different elements of the preamble sequence are exhaustively transmittedin sequence by each oft-repeated symbol of the NPRACH.

In one embodiment, the sequence resource comprises the frequency shifton the symbol groups of NPRACH, by the UE, acquiring, according to afrequency shift value acquisition rule, the frequency shift valueacquisition rule comprises at least one of the following there is thesame frequency shift on top of multiple symbol groups of NPRACH with oneor multiple repetitions, and the value of frequency shift to be acquiredis determined according to the cell identity, there are differentfrequency shift values on top of different symbol groups of NPRACH withone or multiple repetitions, and the value of frequency shift to beacquired is determined according to NPRACH format.

In one embodiment, when a same symbol signal is transmitted in eachsymbol group of an NPRACH, an original cyclic prefix in NPRACH format 0and 1 with additional one or more symbols are aggregated to form a newlonger cyclic prefix, when different signals are transmitted in eachsymbol group of an NPRACH, there is additional cyclic prefix for eachsymbol.

In one embodiment, the sequence resource comprises a scramblingsequence, or the sequence resource comprises a scrambling sequence ontop of a preamble sequence and the scrambling sequences are orthogonaland generated according to a discrete Fourier transform (DFT) matrix.

In one embodiment, the length, generation rule of the scramblingsequence comprise the length of the scrambling sequence is the same asthe number of symbols in one symbol group of NPRACH, the generation ruleis that the same scrambling sequence is used by all the symbol groupswithin an oft-repeated NPRACH of the same UE, or, the length of thescrambling sequence is the same as the length of the symbols of NPRACHwith one repetition, and the generation rule is that the same scramblingsequence is used on top of all the symbols of each NPRACH repetition forone UE, or, the length of the scrambling sequence is the same as thenumber of symbol groups of NPRACH with single repetition, scramblingsequences are superimposed on different symbol groups of one NPRACH forthe UE, and all the symbols of each symbol group are multiplied by thesame element in the scrambling sequence.

In one embodiment, the index of scrambling sequence for a certain UE isdetermined according to a UE identity, or by an eNB, the index ofscrambling sequence is configured through a UE-specific signaling, and,the scrambling sequence is configured to carry digital volumeinformation (DVI), and by the UE, a scrambling sequence index isdetermined according to the DVI.

In one embodiment, the method further comprises the following operationof deciding, according to a first decision rule, whether to reattempt toreport the scheduling request, wherein the first decision rulecomprises, if a random access response (RAR) scrambled by a UE identityis received within an RAR time window, the scheduling request is notattempted to be transmitted, otherwise, deciding whether a terminatingattempt condition is met, if so, terminating attempt and if not,reattempting to transmit the scheduling request.

In one embodiment, the terminating attempt condition is after Ncontinuous attempt and waiting for T NPRACH cycle, attempting again,wherein, the value of the parameters N and T is fixed by a system orconfigured by an eNB.

In accordance with another aspect of the disclosure, an evolved node B(eNB), which is configured to transmit a dedicated physical resource tothe UE, so that a UE performs the method for reporting schedulingrequest in NB IoT systems according to any embodiment of the above.

In accordance with another aspect of the disclosure, a device forreporting scheduling request in NB IoT systems is provided. The deviceincludes an acquisition module configured to acquire a dedicatedphysical resource of a random access channel (NPRACH) used for reportingscheduling request, wherein the dedicated physical resource comprises aplurality of periodic physical resources, a transmitting moduleconfigured to transmit, when a scheduling request is triggered, theNPRACH on the available dedicated physical resource, so as to report thescheduling request.

According to the above method and device for reporting schedulingrequest in NB IoT systems, acquiring a dedicated physical resource of anNPRACH is used for reporting a scheduling request, wherein the dedicatedphysical resource comprises a plurality of periodical physicalresources. When a scheduling request is triggered, the NPRACH istransmitted on the available dedicated physical resource, so as toreport the scheduling request. The dedicated physical resource comprisesa time resource, a frequency resource and a sequence resource. Throughthis dedicated physical resource, the UE can perform reporting ascheduling request in a contention-free random access way, and thecapacity of a preamble sequence is improved and inter-cell interferenceis reduced.

In accordance with another aspect of the disclosure, a method forreporting scheduling request in NB IoT systems is provided. The methodincludes the operations of acquiring the time-and-frequency resources ofthe dedicated physical channel for reporting scheduling request, when ascheduling request is triggered, transmitting the dedicated physicalchannel on the time-and-frequency resource, so as to report thescheduling request, wherein, the dedicated physical channel is anarrowband physical uplink shared channel (NPUSCH) Format 2, or anNPUSCH Format 2 with a high-order modulation mode, or an NPUSCH Format 2using more than two code words, and the additional code words are usedfor indicating the scheduling request and a hybrid automatic repeatrequest (HARQ)-acknowledgement (ACK) information.

In one of the embodiments, the high-order modulation mode comprises aquadrature phase shift keying (QPSK) modulation, and the QPSK symbolcarries HARQ-ACK information and the scheduling request at the sametime.

In one of the embodiments, the time-and-frequency resources aredetermined according to a configuration information and/or a thirdsystem rule, when the time-and-frequency resources are determined atleast according to the configuration information via signaling, thesignaling of the configuration information is carried by a narrowbandphysical downlink shared channel (NPDSCH) or a narrowband physicaldownlink control channel, and the configuration information is used toassign a subcarrier index, repetition number and transmission time tosend the dedicated physical channel of scheduling request, when thetime-and-frequency resources are determined at least according to athird system rule, and the dedicated physical channel is an NPUSCHFormat 2, a subcarrier index for transmitting a scheduling request isacquired according to a subcarrier index transmitting an HARQ-ACK whichis configured in a downlink grant, and the third system rule is used fordefining the frequency interval between the two subcarrier indexes, orfor defining the time interval from an end time of an NPUSCH Format 2bearing an HARQ-ACK to an NPUSCH Format 2 transmitting and bearing ascheduling request, and, when the time-and-frequency resource aredetermined at least according to a third system rule, and the dedicatedphysical channel is an NPUSCH Format 2 with a high-order modulationmode, or is an NPUSCH Format 2 using more than two code words, ascheduling request information and HARQ-ACK information is transmittedusing a time-and-frequency resource for transmitting HARQ-ACK which isconfigured in a downlink grant.

In one of the embodiments, when a scheduling request is triggered,before transmitting the dedicated physical channel on thetime-and-frequency resource so as to report the scheduling request,further deciding, according to a configuration information transmittedby an eNB and/or a second system rule, whether to report the schedulingrequest, deciding, according to a configuration information transmittedby an eNB and/or a second system rule, whether to report the schedulingrequest, if not, continually deciding whether there is a conflictbetween the time-and-frequency resource which is used when a UEtransmits a scheduling request currently and the time-and-frequencyresource which is used when the eNB schedules the UE to transmit anuplink physical channel, if there is a conflict, abandoning thisreporting a scheduling request, or updating, according to a updatingrule, a time frequency which is used when reporting a schedulingrequest, so as to transmit a physical channel for scheduling a request,and, if the UE is currently within an uplink transmitting gap,abandoning the reporting a scheduling request, and, the second systemrule comprises deciding, according to a signaling transmitted by an eNB,whether being allowed to report a scheduling request.

In one of the embodiments, the updating rule comprises deferring toreport a scheduling request, or, using a subcarrier adjacent to asubcarrier used by an NPUSCH Format 2.

According to another aspect, the embodiment of the disclosure providesan eNB, which is configured to transmit configuration information to aUE, so that the UE performs the method for reporting scheduling requestin NB IoT systems according to any embodiment of the above.

According to another aspect, the embodiment of the disclosure provides adevice for reporting scheduling request in NB IoT systems, comprising anacquisition module configured to acquire the time-and-frequencyresources of a dedicated physical channel for reporting schedulingrequest, a reporting module configured to transmit the dedicatedphysical channel on the time-and-frequency resource, so as to report thescheduling request, when a scheduling request is triggered, wherein, thededicated physical channel is a NPUSCH Format 2, or an NPUSCH Format 2with a high-order modulation mode, or an NPUSCH Format 2 using more thantwo code words.

According to the above method and device for reporting schedulingrequest in NB IoT systems, acquiring the time-and-frequency resources ofdedicated physical channel for scheduling request, when a schedulingrequest is triggered, transmitting the dedicated physical channel on thetime-and-frequency resource, so as to report the scheduling request,wherein, the dedicated physical channel is a NPUSCH Format 2, or anNPUSCH Format 2 with a high-order modulation mode, or an NPUSCH Format 2using more than two code words, and the additional code words are usedfor indicating the scheduling request and a HARQ-ACK information. Thededicated physical channel can be an NPUSCH Format 2, the UE cantransmit a scheduling request and/or perform the feedback of HARQ-ACKinformation of the NPDCCH according to a configuration informationand/or a second system rule, and the reporting a scheduling request andthe HARQ-ACK feedback use a same physical channel, but the tworespectively use different time-and-frequency resources and carrydifferent information contents. Through this dedicated physical channel,a scheduling request is reported, competition mechanism of the relatedart is not required to be adopted, and scheduling efficiency can beimproved and system resources are saved.

Other aspects, advantages, and salient features of the disclosure willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses various embodiments of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the disclosure will be more apparent from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 is a structure diagram of a narrowband physical random accesschannel (NPRACH) according to an embodiment of the disclosure;

FIG. 2 is a flowchart of a method for reporting a scheduling request ina narrowband (NB) internet of things (IoT) system according to anembodiment of the disclosure;

FIG. 3 is a flowchart of a method for reporting a scheduling request inan NB IoT system according to an embodiment of the disclosure;

FIG. 4 is a flowchart of a method for reporting a scheduling request inan NB IoT system according to an embodiment of the disclosure;

FIGS. 5A and 5B are schematic diagrams of a plurality of implementationsof NPRACH cover scrambling according to an embodiment of the disclosure;

FIG. 6 is schematic diagram of a plurality of implementations of apreamble sequence according to an embodiment of the disclosure;

FIG. 7 is a schematic diagram of an NPRACH cyclic prefix formataccording to an embodiment of the disclosure;

FIG. 8 is a schematic diagram of another NPRACH cyclic prefix formataccording to an embodiment of the disclosure;

FIG. 9 is a schematic diagram of a device for reporting schedulingrequest in an NB IoT system according to an embodiment of thedisclosure;

FIG. 10 is a schematic diagram of a device for reporting a schedulingrequest in an NB IoT system according to an embodiment of thedisclosure;

FIG. 11 is a schematic diagram of the configuring an NPRACH resource byan evolved node B (eNB) according to an embodiment of the disclosure;

FIG. 12 is a schematic diagram of acquiring, by a user equipment (UE),configuration parameters to obtain time-and-frequency resources of aphysical channel transmitting a scheduling request according to anembodiment of the disclosure; and

FIG. 13 is a schematic diagram of one example of NPRACH cover scramblingused in large cell radius according to an embodiment of the disclosure.

Throughout the drawings, like reference numerals will be understood torefer to like parts, components, and structures.

DETAILED DESCRIPTION

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of variousembodiments of the disclosure as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the various embodiments describedherein can be made without departing from the scope and spirit of thedisclosure. In addition, descriptions of well-known functions andconstructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of thedisclosure. Accordingly, it should be apparent to those skilled in theart that the following description of various embodiments of thedisclosure is provided for illustration purpose only and not for thepurpose of limiting the disclosure as defined by the appended claims andtheir equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

It can be understood by those skilled in the art, the singular forms“a,” “an,” “said” and “the” are intended to include the plural forms aswell, unless expressly stated otherwise. It will be further understoodthat the term “comprising” when used in this specification, specify thepresence of stated features, integers, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, integers, operations, elements, components, and/orgroups thereof. It will be understood that when an element is referredto as being “connected” or “coupled” to another element, it can bedirectly connected or coupled to the other element or interveningelements may be present. In addition, “connected to” or “coupled to” asused herein can comprise wireless connection or coupling. As usedherein, the term “and/or” includes any and all combinations of one ormore of the associated listed items.

It should be understood by one person of ordinary skill in the art that,unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneperson of ordinary skill in the art to which the disclosure belongs. Itshould be further understood that terms, such as those defined incommonly used dictionaries, should be interpreted as having a meaningthat is consistent with their meanings in the context of the prior artand will not be interpreted in an idealized or overly formal senseunless expressly so defined herein.

It should be understood by one person of ordinary skill in the art thatthe term “terminal” and “terminal equipment” as used herein compassesnot only devices with a wireless signal receiver having no emissioncapability but also devices with receiving and emitting hardware capableof carrying out bidirectional communication over a bidirectionalcommunication link. Such devices can comprise cellular or othercommunication devices with a single-line display or multi-line displayor without a multi-line display; personal digital assistants (PDAs),which can include radio frequency (RF) receivers, pagers,internet/intranet accesses, web browsers, notepads, calendars and/orglobal positioning system (GPS) receivers; and/or laptops of the relatedart and/or palmtop computers or other apparatuses having and/orincluding a RF receiver. The “terminal” and “terminal apparatus” as usedherein may be portable, transportable, mountable in transportations(air, sea and/or land transportations), or suitable and/or configured torun locally and/or distributed in other places in the earth and/or spacefor running. The “terminal” or “terminal apparatus” as used herein maybe a communication terminal, an internet terminal, and a music/videoplayer terminal. For example, it may be a PDA, a mobile internet device(MID) and/or a mobile phone with a music/video playback function, or maybe apparatuses such as a smart television (TV) and a set-top box.

FIG. 1 is a structure diagram of a narrowband physical random accesschannel (NPRACH) according to an embodiment of the disclosure.

Referring to FIG. 1 , both the uplink bandwidth and downlink bandwidthof a narrowband (NB) internet of things (IoT) technology system are 200kHz, the transmission bandwidth is 180 kHz, and there are two protectionbandwidth of 10 kHz in front and back, respectively. Compared with longterm evolution (LTE), an NB IoT is generally a single service model,thus, the design of a physical layer is simpler. A downlink physicalchannel (DPCH) merely defines that a narrowband physical broadcastchannel (NPBCH) is used for transmitting a main information block. Anarrowband physical downlink control channel (NPDCCH) is used fortransmitting uplink/downlink grant information, physical downlinkcontrol channel (PDCCH) order and downlink grant of scheduling paginginformation, and indicating to update system message. A narrowbandphysical downlink shared channel (NPDSCH) is used for transmittingdownlink data. Uplink physical channel merely defines that a NPRACH isused for transmitting a random access sequence. A narrowband physicaluplink shared channel (NPUSCH) Format 1 is used for transmitting uplinkdata and NPUSCH Format 2 is used for transmitting 1 bit acknowledgment(ACK)/negative acknowledgement (NACK) information, and indicatingwhether a user equipment (UE) correctly receives downlink data. In termsof physical signal, a downlink merely has narrowband primarysynchronization signal (NPSS), a narrowband secondary synchronizationsignal (NSSS) and a narrowband reference signal (NRS), while an uplinkmerely has demodulation reference signal (DMRS) of NPUSCH Format 1 andNPUSCH Format 2, and is not allowed to transmit periodic or non-periodicuplink detection reference signal.

In order to support an extreme coverage area, the repeated transmissionsof the above physical channels are supported by an NB IoT. For variousdownlink physical channels, except NPBCH being transmitted repeatedlywith a fixed number, the number of repeated transmission of NPDCCH andthe number of repeated transmission of NPDSCH both can be configured,and can be up to 2048. An uplink physical channel, including NPRACH,NPUSCH Format 1 and NPUSCH Format 2, the number of repeated transmissionof which can be configured, can be up to 128. Meanwhile, in terms ofuplink transmission, an NB IoT also supports transmission of a singlesubcarrier. For the most extreme covered UE, a smaller subcarrierinterval of 3.75 kHz can be configured. By decreasing transmissionbandwidth and increasing power spectral density, reliability of uplinktransmission can be promoted efficiently.

In term of physical channel resource allocation, NPBCH, NPSS, NSSS,NPDSCH and NPDCCH (aggregation level 2) all use a full-bandwidth of 180kHz on a 1 ms subcarrier as a basic resource allocation granularity, andmultiplexed transmission of single subframe NPDCCH and single subframeNPDSCH is not supported. NPUSCH Format 1 and NPUSCH Format 2 define,respectively for different transmission bandwidths, scheduled resourceunits on time dimension, for example, single subcarrier transmissionunder a subcarrier interval of 3.75 kHz, single subcarrier transmission,3 subcarrier transmission, 4 subcarrier transmission, 6 subcarriertransmission and 12 subcarrier transmission under a subcarrier intervalof 15 kHz. Except under a subcarrier interval of 15 kHz, a subframe of 1ms is used as a resource unit in 12 subcarrier transmission modes, andunder other transmission modes, a size of each resource unit is morethan 1 ms, that is, transmission across subframes.

NPRACH of an NB IoT is transmitted with a fixed subcarrier interval of3.75 kHz, and a frame structure of NPUSCH is not multiplexed. A singleNPRACH consists of four symbol groups, each of which comprises fiveorthogonal frequency division multiplexing (OFDM) symbols and one cyclicprefix. Each NPRACH transmits an all-ones sequence, the UE estimates afrequency deviation and a timing advance value according to relativefrequency-hopping relation between the symbol groups. FIG. 4 shows aschematic diagram of frequency-hopping transmission of single UE NPRACH.To support repeated transmission of NPRACH, the evolved node B (eNB) canconfigure at most three NPRACH repeated levels, and the UE selects aproper repeated level to perform random access according to adownlink-measured reference signal receiving power and a referencesignal receiving power threshold corresponding to each NPRACH repeatedlevel configured by the eNB. NPRACHs of different repeated levels usedifferent physical resource, and the eNB can configure that NPRACHs ofdifferent repeated levels use a frequency-division or a time-divisionphysical resource on an anchored carrier. FIG. 1 is a structure diagramof a R14-version NPRACH.

Because an NB IoT system does not define a physical uplink controlchannel (PUCCH), and does not support a connected-state UE to transmitscheduling request. In a real system, when a connected-state UE hasuplink data transmission requirement being required to report ascheduling request, it is required to initiate a contention-based randomaccess process, and digital volume information (DVI) indicating a cacheddata amount can be carried in contention solution information (MSG4). Inan NB IoT, contention-based random access process is similar as that inLTE, however, due to limited system frequency resources and becauserepetitions are required if all the physical channel transmission of UEis covered, it will consume more system resources to activate a randomaccess process by scheduling a request report, thus use efficiency ofsystem resources is reduced. Meanwhile, due to limited capacity ofNPRACH and because a system is required to serve large amounts of UEs,it is more difficult to simultaneously support, based on a currentdesign, an idle-state UE to perform initial access and a connected-stateUE to perform random access for purpose of a scheduling request.

FIG. 2 is a flowchart of a method for reporting a scheduling request inan NB IoT system according to an embodiment of the disclosure.

Referring to FIG. 2 , according to one aspect, a method for schedulingrequest in an NB IoT system is illustrated.

In operation S201, the method acquires a dedicated physical resource ofan NPRACH used for reporting scheduling request, wherein the dedicatedphysical resource comprises a plurality of periodical physicalresources.

In operation S202, when a scheduling request is triggered, the methodtransmits the NPRACH on the available dedicated physical resource, so asto report the scheduling request.

According to the above method for reporting scheduling request in NB IoTsystems, acquiring a dedicated physical resource of an NPRACH used forreporting scheduling request, wherein the dedicated physical resourcecomprises a plurality of periodical physical resources. When ascheduling request is triggered, the NPRACH is transmitted on theavailable dedicated physical resource to report the scheduling request.The dedicated physical resource comprises a time resource, a frequencyresource and a sequence resource. Through this dedicated physicalresource, the UE can perform reporting a scheduling request in acontention-free random access way, and the capacity of a preamblesequence is improved and inter-cell interference is reduced.

FIG. 3 is a flowchart of a method for reporting a scheduling request inan NB IoT system according to an embodiment of the disclosure.

Referring to FIG. 3 , according to another aspect, the embodiment of thedisclosure provides another method for reporting scheduling request inNB IoT systems.

In operation S301, the method acquires the time-and-frequency resourcesof the dedicated physical channel for reporting scheduling request.

In operation S302, when a scheduling request is triggered, the methodtransmits the dedicated physical channel on the time-and-frequencyresource to report the scheduling request. The dedicated physicalchannel is an NPUSCH Format 2, or an NPUSCH Format 2 with a high-ordermodulation mode, or an NPUSCH Format 2 using more than two code words.

According to the above method for reporting scheduling request in NB IoTsystems, the time-and-frequency resources of the dedicated physicalchannel for reporting scheduling request is acquired. When a schedulingrequest is triggered, the dedicated physical channel is transmitted onthe time-and-frequency resource to report the scheduling request. Thededicated physical channel is an NPUSCH Format 2, or an NPUSCH Format 2with a high-order modulation mode, or an NPUSCH Format 2 using more thantwo code words. The dedicated physical channel can be an NPUSCH Format2, the UE can transmit a scheduling request and/or perform the feedbackof hybrid automatic repeat request (HARQ)-acknowledgement (ACK)information of the PDCCH according to a configuration information and/ora second system rule, and the reporting a scheduling request and theHARQ-ACK feedback can use a same physical channel, but the tworespectively use different time-and-frequency resources and carrydifferent information contents. Through this dedicated physical channel,because a scheduling request is reported, competition mechanism of therelated art is not required to be adopted, and scheduling efficiency canbe improved and system resources are saved.

Embodiment 1

FIG. 4 is a flowchart of a method for reporting a scheduling request inan NB IoT system according to an embodiment of the disclosure.

Referring to FIG. 4 , a method for reporting scheduling request in NBIoT systems is described, which reports the scheduling request throughcontention-free random access.

In operation S401, the method acquires a dedicated physical resource ofan NPRACH used for reporting scheduling request, the dedicated physicalresource comprises a plurality of periodical physical resources. Forexample, the dedicated physical resource comprises a time resource, afrequency resource and a sequence resource.

In operation S402, the method transmits the NPRACH on the availablededicated physical resource to report the scheduling request.

In operation S403, the method decides whether to reattempt to report thescheduling request according to a first decision rule. If the methodreattempts to report the scheduling request, the method proceeds tooperation S404 or, otherwise proceeds to operation S405.

In operation S404, after the reporting the scheduling request iscompleted, the scheduling request is not attempted to be transmitted.

In operation S405, the method decides whether a terminating attemptcondition is met. If the terminating condition is met, the methodproceeds to operation S406. If the terminating condition is not met, themethod returns to operation S401 to reattempt to transmit the schedulingrequest.

In operation S406, the method terminates attempting to report thescheduling request.

For a connected-state UE, an enhanced NPRACH is transmitted on thededicated time-and-frequency resource to perform uplink the schedulingrequest. Then, by the UE, if a random access response (RAR) scrambled bya UE identifier is received within an RAR time window, the reporting ascheduling request is completed. Otherwise, the UE performs the processagain, until a terminating attempt condition is reached or the reportinga scheduling request is completed.

The terminating attempt condition can be fixed or configured by an eNB.For example, the rule is assumed to be: after N continuous attempt andwaiting for T NPRACH cycle, transmitting again, wherein the value of theparameters N and T is fixed by a system or configured by an eNB. Theconfigured parameters can be configured independently for the repeatedlevel of each NPRACH, or can be configured to applicable to commonparameters of all repeated levels.

Certainly, a system also cannot configure a terminating attemptcondition, if at this time after the UE currently fails to transmit ascheduling request, that is, continually performs the abovecontention-free random access process, until the reporting a schedulingrequest is completed.

A possible enhancement of NPRACH can be adding a scrambling sequence ontop of the preamble of NPRACH, and by using orthogonal scramblingsequence, thereby allowing multiplexing transmission of multi-UE NPRACHsin the same time-and-frequency resource. In another example, theorthogonal scrambling sequences are used to carry DVI so that ascrambling sequence index is determined by the UE according to the DVI,which is to indicate the UE's uplink data buffer. For example, thelength of the scrambling sequence of the enhanced NPRACH is assumed tobe N, different UEs can be allowed to use different orthogonalscrambling to transmit an NPRACH on a same time-and-frequency resource.The used scrambling sequence can be determined according to a UEidentity (for example, cell radio network temporary identifier(C-RNTI)), for example, I_(Mask)=N_(UEID) mod (N−1), wherein, N_(UEID)is the UE identity, I_(Mask) is the scrambling sequence allocated to theUE, or the scrambling sequence used by the UE can be configured by aneNB according to a UE dedicated signaling, and the mod is a modulusfunction. An example of the orthogonal scrambling sequence carrying DVIis as follows: the length of the scrambling sequence of the enhancedNPRACH is assumed to be N, an all-ones sequence used by acontention-based NPRACH is excluded, the number of the availableorthogonal scrambling sequences of the NPRACH for reporting schedulingrequest is N−1, the orthogonal scrambling sequence to be used isselected by a UE according to the DVI, the sequence number of theorthogonal scrambling sequence selected by the UE is determined by aneNB according to a way of blind-detection, and the DVI carried by the UEunlink scheduling request.

In addition to improve the capacity of the NPRACH, orthogonal scramblingcan also be used for the NPRACH in initial access to support a largercell radius. The length, generation rule and superimposed mode of thescrambling sequence are all fixed by the system, with different possibleimplementations. The frequency-hopping format of the current NPRACH inRelease 13 and 14 can be inherited when used for scheduling request, orwithout frequency hopping, that is, the same subcarrier is used fordifferent NPRACH repetitions and also for the different symbol groupswithin one NPRACH. For example, taking an example of reusing the NPRACHfrequency-hopping pattern in Release 13 and 14 specification, FIG. 5shows a schematic diagram providing different implemented ways of NPRACHscrambling sequence. Specific manners will be described as below withreference to FIG. 5 .

FIGS. 5A and 5B are schematic diagrams of a plurality of implementationsof NPRACH cover scrambling according to an embodiment of the disclosure.

1. According to an example embodiment of FIG. 5A, the length of theorthogonal scrambling sequence is the same as the number of symbolswithin one symbol group of NPRACH, that is, the length is 5, the samescrambling sequence is shared by all the symbol groups within an NPRACHwith one or multiple repetitions for the same UE, and the NPRACHpreamble sequence will be covered by orthogonal scrambling with vectordot product, that is [c₁*p₁, . . . , c₅*p₅] or [c₁*p₁ ^(H), . . . c₅*p₅^(H)], wherein, c=[c₁, . . . , c₅] is a scrambling sequence, p=[p₁, . .. , p₅] is a partial preamble sequence of a symbol group of the NPRACH,x^(H) denotes a conjugate of a plural x, and the same method to usescrambling sequence on top of NPRACH preamble can be used in thefollowing other implementations of NPRACH scrambling, the expressionformula of which is slightly different due to different lengths of theorthogonal scrambling.

2. According to another example embodiment of FIG. 5A, the length of theorthogonal scrambling is the same as the number of symbols of the NPRACHwith one repetition, that is, the length is 20, and the same scramblingsequence is used for multiple NPRACH repetitions of the same UE.

3. The length of the orthogonal scrambling is the same as the number ofsymbol groups of NPRACH with single repetition, that is, the length is4, scrambling sequences are superimposed on different symbol groups ofone NPRACH for the UE, and all the symbols of each symbol group aremultiplied by the same element in the scrambling sequence. The elementsof a scrambling sequence can be same or different. The elements of thescrambling sequence for the neighboring symbol groups can have the samevalue. For example, according to an example embodiment in scheme 3 ofFIG. 5B, it may let c₀=c₁, c₂=c₃, that is, the first two symbol groupsand the last two symbol groups are enabled to be superimposed withscrambling sequence elements with same value, respectively, and thisdesign can reduce the peak-to-average power ratio of the NPRACH.

4. The orthogonal scrambling is used for transmitting an NPRACH onmultiple subcarriers, the length of the scrambling sequence is the samewith the number of the subcarriers used by the NPRACH, a scramblingsequence is superimposed on different subcarriers in the same OFDMsymbol, and according to an interval between subcarriers, the NPRACH canhave different cyclic prefix lengths, so as to support a larger cellradius. For example, according to another example embodiment in scheme 4of FIG. 5B, an example that a subcarrier interval is 1.25 kHz isprovided, at this time, the cyclic prefix length can be 800 us forsupporting a cell radius of maximum 120 km. One symbol group in theNPRACH contains one symbol, each symbol contains three resource elementsof 1.25 kHz and a scrambling sequence with the length being 3 issuperimposed on the three resource elements of each symbol. The lengthof a scrambling sequence is given, the scrambling sequence can begenerated based on different rules, and an orthogonal sequence or aquasi-orthogonal sequence is generated. For example, a discrete Fouriertransform (DFT) matrix can be used, and except an all-ones sequence,each of remaining sequences can be the scrambling sequence of the NPRACHfor purpose of reporting a scheduling request. For example, as thelength is 5, the scrambling sequence formula generated based on a DFTmatrix is

${c_{n} = \left\lbrack {1,\ e^{{- j}\frac{2{\pi \cdot n}}{5}},e^{{- j}\frac{2{\pi \cdot 2}n}{5}},e^{{- j}\frac{2{\pi \cdot 3}n}{5}},e^{{- j}\frac{2{\pi \cdot 4}n}{5}}} \right\rbrack},{n = 1},\ldots,4.$For scheme 1 and scheme 2 to reduce the peak-to-average power ratio, theelement used when generating a scrambling sequence can be a modulatedsymbol of

$\frac{\pi}{2}$binary phase shift key (BPSK), or a modulated symbol of

$\frac{\pi}{4}$quadrature phase shift key (QPSK) or modulated symbol of

$\frac{\pi}{8}$phase shift key (8PSK). In another example, to ensure the orthogonalitybetween subcarriers in the scenario of larger cell radius, the severalcontinuous symbols can be designed to carry the same elements ofscrambling sequence while generating the scrambling sequence, which canbe applied into all the above implementations of scrambling sequence. Inthis way, the front symbols can serve as the cyclic prefix of the symbolbehind. Taking the first NPRACH scrambling sequence implementation as anexample, two corresponding instances of scrambling sequence are shown inFIG. 13 .

A UE is required to transmit, on the dedicated time-and-frequencyresource thereof, an NPRACH for scheduling request. The dedicatedtime-and-frequency resource at least includes the index of startsubcarrier to transmit NPRACH, and the dedicated time resource at leastincludes the start subframe index and repetition number to transmitNPRACH. The dedicated time resource can be obtained by a UE according tothe first system rule, or can be explicitly configured by the eNB. Forexample, the dedicated time resource is configured via a UE-specificsignaling, and one possible method of explicit configuration can be seenin Embodiment 5. Similarly, the dedicated frequency resource can also beobtained by the UE according to the first system rule, or can beexplicitly configured by eNB. For example, the dedicated frequencyresource is configured via a UE-specific signaling, which at leastincludes the start subcarrier index. The configuration method of adedicated time resource and frequency resource can be different, whichcan be any combination of the above configuration methods. For instance,the repetition number and start subcarrier index are obtained by UEbased on the first system rule, and the start subframe (and/orperiodicity of scheduling request) is indicated by explicit signaling.In the following, several examples of the first system rule to determinethe dedicated resource will be provided.

First, the first system rule for determining frequency resource can bethat the UE sends NPRACH for a scheduling request on the same subcarrierused in the initial access. The first system rule for determining timeresource can be that the UE obtain the repetition number and/or startsubframe of NPRACH for a scheduling request based on the configurationof NPRACH in the initial access. Or the first rule can determine thestart subframe and/or start subcarrier of the NPRACH for schedulingrequest according to the UE identifier. For example, a sametime-and-frequency resource can be assumed to be multiplexed by multipleUEs to transmit an NPRACH for a scheduling request. One rule can beconfigured as the follows: a location of a dedicated time-and-frequencyresources are computed by a UE according to a UE identity (for example,C-RNTI) of a UE, wherein, the location (I_(sc), I_(period)) of atime-and-frequency resource can be determined by a lookup tableaccording to a value of (N_(UEID)/(N_(Mask)−1)) mod (N_(sc)×N_(period)).The scrambling sequence index is I_(Mask)=N_(UEID) mod (N_(Mask)−1),I_(sc) is an index of a subcarrier used when transmitting an NPRACH,I_(period) is an index of an opportunity of transmitting an NPRACH (theperiod of an NPRACH is used as a basic unit, and one period of an NPRACHis between neighbor random access opportunities), N_(UEID) is a UEidentity, N_(Mask) is length of a scrambling sequence, N_(SC) is numberof subcarriers configured by a repeated level of a UE-used NPRACH, andthe UE can multiplex the repeated level of an NPRACH used when the UEperforming initial access so as to perform random access for schedulingrequest purpose, and N_(period) is number of opportunities of randomaccess.

Or, in the above examples of configuration, one of thetime-and-frequency resource can be used as parameter explicitlyconfigured by an eNB, and another parameter can be acquired according toa system rule. For example, a dedicated time resource indicates thatI_(period) is used as an explicitly configured parameter, and thededicated frequency resource indicates that it can be acquired accordingto the following formula: I_(sc)=(N_(UEID)/(N_(Mask)−1)) mod (N_(sc)).In another example, the dedicated frequency resource indicates thatI_(SC) is used as an explicitly configured parameter, and the dedicatedfrequency resource indicates that it can be acquired according to thefollowing formula: I_(period)=(N_(UEID)/(N_(Mask)−1)) mod (N_(Period)).

For all the above examples, if a DVI is indicated by using a scramblingsequence index, which is not used for transmitting an NPRACH by multi-UEmultiplexing, the formulas of the above examples are required to bemodified. For example, for all the dedicated time resource and thefrequency resource being acquired through a system rule, at this time,the location (I_(sc), I_(period)) of a time-and-frequency resource canbe determined by a lookup table according to a value of (N_(UEID)) mod(N_(sc)×N_(Period)).

Embodiment 2

In this embodiment, a method for reporting scheduling request in an NBIoT system is described, which improves the capacity of a preamblesequence and reduces inter-cell interference through an enhanced NPRACH.

A UE acquires relevant parameter configuration information of a preamblesequence of a cell-level NPRACH, and determines the preamble sequenceused in this random access process (which includes but is not limited toan initial access process, a PDCCH order-triggered random accessprocess, and the random access process used for reporting schedulingrequest in Embodiment 1) according to a preamble sequence acquisitionrule.

The preamble sequence acquisition rule can be a system-given rule. Forexample, if a cell-level configured preamble sequence is assumed to be aunique sequence, all the UEs within the cell all use the preamblesequence, and the index of the cell-level preamble sequence can becomputed according to a cell ID. For example, i=N_(PCID) modN_(preamble), where i is the preamble sequence index used by all the UEsof the cell, N_(PCID) is the cell identity, and N_(preamble) is thenumber of the preamble sequence in the configured preamble sequence set.Cell-level configured preamble sequences are assumed to be multiple,that is, one preamble sequence set. The set index can also be computedaccording to a cell identity. For example, i_(group)=N_(PCID) modN_(group), where i_(group) is the index of the configured preamblesequence set of the cell, N_(PCID) is the cell identity, and N_(group)is the number of the configured preamble sequence set. At this time, bythe certain rule based on which the UE selects a preamble sequence, oneof a plurality of configured preamble sequences can be selected by theUE to perform random access, or when the UE performs different types ofrandom access processes, a preamble sequence is selected based ondifferent rules. For example, in a contention-based random accessprocess, the UE randomly selects one of a plurality of configuredpreamble sequences. In a contention-free random access process, the UEacquired the used preamble sequence according to eNB explicitlyconfiguration or a certain system rule, and the explicitly configurationmode and system rule are the same with that described in Embodiment 1.Preamble sequences (or preamble sequence sets) configured in differentcells can be different or not completely same, which is used forreducing inter-cell interference when an eNB receives an NPRACH.

A preamble sequence format, comprising length and sequence generationtype, can be fixed by a system and can have different implementationmodes below.

1. the length of the preamble sequence is the same with number ofseveral repetitions of the NPRACH, the number of the several repetitionsis a value fixed by the system, which is set as M_(rep), the value ofM_(rep) is the submultiple of the number of the total repetitions, andthe maximum value is the number of the total repetitions of the NPRACH.During a single repetition of the NPRACH, a same element of the preamblesequence is transmitted by each symbol, and during the M_(rep)repetitions, each element is transmitted in preamble sequence in eachrepetition of the NPRACH. For a plurality of repeated transmission ofthe NPRACH, M_(rep) repetitions are used as a granularity unit toperform repetition for the preamble sequence.

2. the length of the preamble sequence is the same as the number of thesymbol groups of the NPRACH, that is, the length is 4, one element ofthe preamble sequence is transmitted repeatedly by all symbols of onesymbol group of the NPRACH, each element of the preamble sequence istransmitted in sequence according to a sequence of symbol groups in thesingle NPRACH, and a same preamble sequence is transmitted with in eachrepetition of the NPRACH.

3. the length of the preamble sequence is the same with number of thetotal symbols of several repetitions of the NPRACH, the number of theseveral repetitions is a value fixed by the system, which is set asM_(rep), the value of M_(rep) is the submultiple of the number of thetotal repetitions, and the maximum value is the number of the totalrepetitions of the NPRACH. During M_(rep) repetitions, differentelements of the preamble sequence are transmitted in sequence by eachoft-repeated symbol of the NPRACH. For a plurality of repeatedtransmission of the NPRACH, M_(rep) repetitions are used as agranularity unit to perform repetition for the preamble sequence.

FIG. 6 is schematic diagram of a plurality of implementations of apreamble sequence according to an embodiment of the disclosure.

Referring to FIG. 6 , the schematic diagram of the three implementationmodes of the preamble sequence formats is illustrated. When the value ofall the elements of the preamble sequence is 1, the implementationeffect of the three implementation methods is same. The rule of thegeneration of the preamble sequence is the same with that of thegeneration of the scrambling sequence in Embodiment 1, and will not berepeated here.

FIG. 7 is a schematic diagram of an NPRACH cyclic prefix formataccording to an embodiment 2.

Referring to FIG. 7 , when a same symbol is transmitted in each symbolgroup of an NPRACH, an original cyclic prefix in an existing NPRACHformat and one or more symbol are aggregated to form a new cyclicprefix, which is used for supporting a larger cell radius. For example,a cyclic prefix of an NPRACH Format 1 and first two symbols areaggregated to form a new cyclic prefix, used for supporting a cellradius larger than 100 km.

FIG. 8 is a schematic diagram of another NPRACH cyclic prefix formataccording to an embodiment 2.

Referring to FIG. 8 , when different symbols in each symbol group of anNPRACH are transmitted, a cyclic prefix is required to be added beforeeach symbol to avoid inter-symbol interference. In another example, thefront symbol(s) are used as the cyclic prefix of the latter symbol ifthere are same continuous symbols within one symbol group of NPRACH. Atthe same time, the NPRACH format can use scrambling scheme 4 of NPRACHscrambling is illustrated in the embodiment described with respect toFIG. 5 . The NPRACH format can also be based on the current NPRACHformat, and a fixed frequency offset is added on the neighboring symbolgroups of NPRACH. Take an example of 1.25 kHz frequency offset, and thenthe time signals of the I_(th) symbol group can be generated accordingto the following formula:

s_(i)(t) = β_(NPRACH)e^(j2π(n_(sc)^(RA)(i) + Kk₀ + 1/2 + Δ_(i))Δf_(RA)(t − T_(CP)))

Wherein, Δ_(i) denotes the frequency shift on the symbol groupβ_(NPRACH) is an amplitude scaling factor, k₀=−N_(sc) ^(UL)/2 andK=Δf/Δf_(RA) denotes a ratio of a subcarrier spacing Δf of an uplinkdata channel to a subcarrier spacing Δf_(RA) of an NPRACH, N_(sc) ^(UL)denotes number of uplink subcarriers, n_(sc) ^(RA)(i) denotes an indexof an NPRACH subcarrier, and ñ_(sc) ^(RA)(i−1) is a subcarrier offset ofan NPRACH symbol group frequency hopping.

In this example, the values of frequency shift (i.e., Δ_(i)) fordifferent symbol groups can be either the same or different. One exampleof different frequency shift for different symbol group can be

$\Delta_{l} = \left\{ {\begin{matrix}{{- 1}/4} & {{{i{mod}4} = 1},{{3{and}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}{mod}2} = 0}} \\{1/4} & {{{i{mod}4} = 1},{{3{and}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}{mod}2} = 1}}\end{matrix},} \right.$which represents −1.25 kHz frequency shift between symbol group 0 andsymbol group 1, and 1.25 kHz frequency shift between symbol group 2 andsymbol group 3. The value of Δ_(i) is determined by the ratio offrequency shift and subcarrier spacing of NPRACH, e.g., when thefrequency shift is 1.25kHz and the subcarrier spacing of NPRACH is 3.75kHz, then Δ_(i) is −¼. The value of frequency shift can be obtained bythe UE according to cell identity and/or a definition of NPRACH format,e.g., the frequency shift is determined by N_(ID) ^(cell) modN_(NPRACH,fs,) where N_(ID) ^(cell) is cell identity, N_(NPRACH,fs) isthe number of candidate frequency shift values, mod denotes the Moduluscalculation; or, according to the configured NPRACH format by eNB toobtain different value of frequency shift on different symbol groups asthe above example; or in a combined way, to obtain a unified frequencyshift of all the symbol groups according to cell identity and thenobtain the additional frequency shift for neighboring symbol groupsaccording to NPRACH format.

Except Δ_(i), the value and the specific meaning of all the aboveparameters can refer to the 3GPP TS36.211 V13.3.0 specification. Theabove method of frequency shift on NPRACH symbol groups can be appliedwith any frequency hopping pattern.

An eNB can independently configure different NPRACH Formats for eachrepeated level of each NPRACH, which is used for performance detectionof the random access channels (RACHs) of a nearer UE and a farther UE tothe eNB simultaneously, in the case of a larger cell radius.

In another example, a UE can acquire at least two NPRACH formatconfigurations and a configuration of each NPRACH Format to one or moreNPRACH repeated levels. The UE selects an NPRACH Format and a repeatedlevel according to a certain rule, and the rule can be one to one fixedcorrespondence between an NPRACH Format and an NPRACH repeated level.For example, the eNB configures two NPRACH Formats, which may be NPRACHFormat 0 and NPRACH Format 1. The system rule is that the NPRACH Format1 is applicable to a repeated level of a repeated number of an NPRACHbeing larger than a certain threshold, while the NPRACH Format 0 isapplicable to a repeated level of repeated number of an NPRACH beinglower than the threshold, and the threshold can be fixed or informed byan eNB through a signaling. After the UE determines the selectedrepeated level of the NPRACH according to a reference signal receivingpower obtained by downlink measurement, the NPRACH Format is determinedaccording to the repeated level. In another example, the UE firstselects an acquiescent NPRACH Format, then decides whether to update theNPRACH Format according to a certain rule, and retransmits a randomaccess channel. The rule of updating NPRACH Format can be that, a UErandom access fails, the attempts of the random access have reached amaximum number, and the repeated level of an NPRACH selected currentlyby the UE is a level when a system configures a maximum repeated levelof an NPRACH, and a random access process is reinitiated after theNPRACH Format is updated.

In yet another example, the configuration mode of an eNB may combine theabove two configurations. For example, different NPRACH Formats can beindependently configured for one or more repeated levels of an NPRACH inall repeated levels of an NPRACH of a cell by an eNB. For a repeatedlevel of an NPRACH not explicitly configured by an NPRACH Format, theNPRACH Format is determined by an UE according to a certain system rule.For example, the system rule can be that, as described above, there iscorrespondence between an NPRACH Format and a repeated level of anNPRACH. In another system rule, a certain NPRACH Format, such as NPRACHFormat 0, is fixedly used.

The scrambling enhanced-mode of NPRACH in Embodiment 1 can be combinedwith the preamble sequence configuration in this embodiment, or they areused respectively and independently.

Embodiment 3

In this embodiment, a method for reporting scheduling request in an NBIoT system is described, which uses a dedicated physical channel (NPUSCHFormat 2) to transmit a scheduling request. After receiving anNPDCCHends, a UE can perform the feedback of hybrid automatic repeat request(HARQ)-ACK information of the PDCH and/or transmit a scheduling requestaccording to a configuration information and/or a certain rule.

Way 1:

The transmission including a scheduling request can use an NPUSCH Format2, which uses a same physical channel with the HARQ-ACK feedback, butthe two respectively use different time-and-frequency resources andcarry different information contents. When the NPUSCH Format 2 is usedfor reporting a scheduling request, the code word formats of an uplinkcontrol information can be shown in Table 1, that is, 1 bit schedulingrequest information is transmitted:

TABLE 1 Scheduling Scheduling request code words request bit <b₀, b₁,b₂, . . . , b₁₅> 0 <0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,> 1<1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,>

In another example, the orthogonal code words are used for carryingmulti-bit DVI. The codeword sequences is generated to ensureorthogonality of modulated codeword sequences (e.g., Walsh code), toensure the semi-orthogonality of the aggregated modulated codewordsequences and demodulation reference signal sequences, to adoptsemi-orthogonal complex sequences, e.g., m sequence, or to adoptorthogonal complex sequences (e.g., DFT sequence). Table 2 provides acode word format example of transmitting 2 bit DVI:

TABLE 2 Scheduling request code words DVI bit <b₀, b₁, b₂, . . . , b₁₅>00 <0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1,> 01 <1, 1, 1, 1, 1,1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,> 10 <0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,1, 0, 1, 0, 1,> 11 <1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,>

In another example, the eNB configures a dedicated scheduling requestcode word for each UE, and the scheduling request is reported by the UE.That is, the NPUSCH Format 2 carrying the dedicated scheduling requestcode word is transmitted on the configured time-and-frequency resource,otherwise, the NPUSCH Format 2 is not transmitted. At this time,different UEs can transmit a scheduling request in a NPUSCH Format 2 ata same time-and-frequency resource location, and scheduling requests ofa plurality of UEs are recognized by an eNB through blind detection.Table 3 provides an example of allocating, by an eNB, multi-UEscheduling request code word:

TABLE 3 Scheduling request code words UE index <b₀, b₁, b₂, . . . , b₁₅>1 <0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1,> 2 <1, 1, 1, 1, 1, 1,1, 1, 1, 1, 1, 1, 1, 1, 1, 1,> 3 <0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,1, 0, 1,> 4 <1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0,>

In this method, a same fixed scheduling request code word can be enabledto be used by all the UEs, thus the time-and-frequency resource locationused while different UEs transmit scheduling requests is required to bedifferent. At this time, the eNB blind detects and recognizes ascheduling request of a UE at each UE-specific time-and-frequencyresource location.

The time-and-frequency resources, which are used for transmitting anNPUSCH Format 2 including a scheduling request, can be determinedaccording to a configuration information and/or a third system rule. Thetime-and-frequency resources at least include the start subframe (and/orscheduling request periodicity), index of subcarrier, and repetitionnumber. For example, when a scheduling request information istransmitted at a time-and-frequency resource location that is configuredby a UE-specific signaling, wherein the UE-specific signaling can betransmitted by an NPDSCH or an NPDCCH. When it is transmitted by anNPDCCH, the UE-specific signaling can be carried in the downlink grant,and is a dynamic configuration information, and is a quasi-staticconfiguration when it is transmitted by the NPDSCH.

In this embodiment, when the dedicated physical channel is an NPUSCHFormat 2, the repetition number of dedicated channel for schedulingrequest can be obtained based on that for HARQ-ACK, e.g., use the samerepetition number, or the repetition number for HARQ-ACK transmissionadded/multiplexed by an offset, which is fixed or configured by eNB.Under the same condition, a subcarrier index for transmitting ascheduling request can be acquired according to a subcarrier indextransmitting an HARQ-ACK which is configured in a downlink grant. Thethird system rule is used for defining the frequency interval betweenthe two subcarrier indexes, or for defining the time interval from anend time of an NPUSCH Format 2 bearing an HARQ-ACK to an NPUSCH Format 2transmitting and bearing a scheduling request. The details are asfollows:

The configuration information may be location of time-and-frequencyresource while being explicitly configured. For example, the methoddescribed with respect to Embodiment 5 can be indicated in a subcarrierindex and transmission or a carrier, a subcarrier index and transmissiontime. The transmission time can be an index of time unit of transmittinga scheduling request, and the time unit of transmitting a schedulingrequest can be a fixed period of time, for example, a subframe or afixed number of subframes. The transmission time can also be definedaccording to timing relationship, for example, the time interval ofindicating how long the NPUSCH Format 2 bearing a scheduling request istransmitted from the end time of the NPUSCH Format 2 bearing HARQ-ACK.The indicating of the used carrier signaling contents can be a frequencyinterval indicating the used carrier and the anchored carrier (ornon-anchored carrier used for current uplink/downlink data transmissionby a UE), or allow a UE to use a fixed-location carrier to transmit ascheduling request. At this time, the frequency resource configurationcan merely explicitly indicate a subcarrier index on a carrier that isused for transmitting a scheduling request, and the fixed-locationcarrier can be a non-anchored carrier having a fixed frequency offsetwith the anchored carrier.

Similarly, the time-and-frequency resource location of a physicalchannel for transmitting a scheduling request can also be implicitlyindicated according to a third system rule, for example, according tocarrier location, configured in downlink grant, for transmittingHARQ-ACK and a subcarrier index, acquiring the subcarrier location andthe subcarrier index, for transmitting a scheduling request. The systemrule can be that the two subcarriers are located on a same carrier andthere is a fixed interval between indexes, or the two carriers have afixed frequency offset and the subcarrier indexes are same. As for thetime resource, the NPUSCH Format 2 including a scheduling request can beenabled to be transmitted, after a fixed time from the end time of theNPUSCH Format 2 bearing HARQ-ACK. Meanwhile, a resource configurationmethod with two dimensions of time and frequency can also adopt anexplicit-and-implicit-combined mode, that is, the one is configuredexplicitly and another is acquired according to a system rule.

After acquiring a time-and-frequency resource configuration fortransmitting a scheduling request, a UE can decide whether to transmitthe scheduling request according to a configuration and/or a secondsystem rule. For example, the second system rule can be deciding whetherbeing allowed to report a scheduling request according to a signalingtransmitted by a UE.

The decision process can be that an eNB transmits a signal to indicatewhether the UE is allowed to transmit a scheduling request. Afteracquiring an indication of being allowed to transmit a schedulingrequest, a UE transmits a physical channel carrying a scheduling requestbit on the configured time-and-frequency resource, and carrying bit 1 inTable 1 when there is a scheduling request and carrying bit 0 in Table 1when there is no scheduling request.

The decision process can be that an eNB transmits a signal to indicatewhether the UE is allowed to transmit a scheduling request. Afteracquiring an indication of being allowed to transmit a schedulingrequest, the UE decides whether to transmit a scheduling requestaccording to a second system rule. The second system rule can be that,only when the HARQ-ACK bit requiring feedback is 1 (that is, ACKinformation), the UE transmits a physical channel including a schedulingrequest bit, and at this time, the physical channel including anHARK-ACK information can be transmitted or not be transmitted. Forexample, when the two transmission times configured by the two physicalchannels have an overlap to each other, and the physical channel bearingHARK-ACK information is not transmitted when a scheduling request istransmitted.

The decision process can also be that a UE decides whether to transmit ascheduling request merely according to a second system rule, and thesecond system rule is same as that in the above described.

A may UE decide whether the transmitting of a scheduling request iscompleted according to a certain rule (e.g., a second decision rule),consider the transmitting a scheduling request is completed when the UEreceives an uplink grant within a time window, and the schedulingrequest is not attempted to be transmitted. Otherwise, the schedulingrequest is continually reattempted to be transmitted. And thetime-and-frequency resource configuration mode used for reattempting totransmit the scheduling request can be same or different with thetime-and-frequency resource configuration mode in the initialtransmission, and the available configuration mode can be the abovedescribed.

Way 2:

The transmitting of a scheduling request can use a dedicated physicaluplink channel to transmit piggybacked scheduling request bit withHARQ-ACK on the same time-and-frequency resource.

When the dedicated physical channel is an NPUSCH Format 2 with ahigh-order modulation mode or an NPUSCH Format 2 using more than twocode words, the time-and-frequency resource, configured in a downlinkgrant, is used for transmitting scheduling request and HARQ-ACKinformation.

The dedicated physical uplink channel can be an NPUSCH Format 2introducing a high-order modulation mode (for example, quadrature phaseshift keying (QPSK) modulation), which simultaneously carries 1 bit ofscheduling request (or, multi-bit DVI) and 1 bit of HARQ-ACKinformation, wherein the code words of the scheduling request bit isshown in Table 1 (DVI code words shown in Table 2). There are differentways for generating QPSK modulation signals. For example, the code wordsof a scheduling request bit is assumed to be [b₀, b₁, . . . , b₁₅], andthe code words of an HARQ-ACK bit is [a₀, a₁, . . . , a₁₅], 16 QPSKmodulation signals are generated in sequence based on (a_(n)b_(n)), n=0,. . . , 15. One example for QPSK constellation mapping can be asfollows. The real part of a QPSK can be enabled to carry the code wordsof the HARQ-ACK bit, while the imaginary part carries the code words ofthe scheduling request bit, that is, the n^(th) QPSK modulation symbolis

${s_{n} = {\frac{1}{\sqrt{2}} \cdot \left( {a_{n} + {i \cdot b_{n}}} \right)}},$wherein i=√{square root over (−1)} is the imaginary unit. In anotherexample, the QPSK constellation mapping method in 3GPP TR36.211specification can also be used. The code words of HARQ-ACK can inheritthe existing method, i.e., to use 16-length all “0” sequence and all “1”sequence to indicate NACK and ACK respectively. The code words ofscheduling request is also designed to carry 1-bit information, as inTable 1, to use 16-length all “0” sequence and all “1” sequence toindicate non-existence and existence of scheduling request,respectively.

Or, after the code words of the HARQ-ACK bit and the code words of thescheduling request bit are arranged and combined in a certain order, thecombined sequences are modulated, the combined sequence is assumed to be[c₀, c₁, . . . , c₃₁], wherein c_(n)=a_(k) or c_(n)=b_(k), 0≤k≤15.Again, 16 QPSK modulation signals are generated in sequence based on(c_(2i)c_(2i+1)), i=0, . . . , 15. The method of QPSK constellationmapping is the same as above. To reduce the peak to average power ratio,phase rotated QPSK,

${e.g.},{\frac{\pi}{4} - {{QPSK}{or}\frac{\pi}{2}} - {QPSK}},$can be used, and the signal can be generated with the same method ofuplink signal generation in Release 13 and 14 NB-IoT.

The dedicated physical channel can also be an NPUSCH Format 2 carryingan on-off scheduling request signal. For example, when a UE is requiredto transmit a scheduling request, the QPSK signals are transmitted onthe dedicated physical channel. The code word corresponding to thetransmitted HARQ-ACK bit is assumed to be [a₀, a₁, . . . , a₁₅], and thecode word corresponding to the scheduling request signal is [b₀, b₁, . .. , b₁₅]. Again, 16 QPSK modulation signals are generated in sequencebased on (a_(n)b_(n)), n=0, . . . , 15, and the method of QPSKconstellation mapping is the same as above. The code words forscheduling request carries on-off signal, as in Table 4, i.e., the UEindicate existence or non-existence of scheduling request by sending ornot sending the code word. Similarly, phase rotated modulation can beused to reduce peak to average power ratio, as described above.

TABLE 4 Scheduling Scheduling request code words request bit <b₀, b₁,b₂, . . . , b₁₅> 1 <1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,>

When the UE transmits HARQ-ACK without a scheduling request, themodulation method of the dedicated physical channel is BPSK, which isexactly the same with the NPUSCH Format 2 for HARQ-ACK only transmissionin Release 13 and 14 NB-IoT. When carrying an on/off scheduling requestsignal, the dedicated physical channel carrying QPSK signals can beconfigured with different repetition number from HARQ-ACK onlytransmission because their detection performances are different. Whenthe off signal is transmitted (that is, a scheduling request is nottransmitted), the detection performance is better, and the dedicatedphysical channel can be transmitted with less repetitions to reduceenergy consumption of UE. The repetition number for the HARQ-ACK onlytransmission and the HARQ-ACK piggybacked with scheduling request signalcan be configured by radio resource control (RRC) signaling,respectively. In another example, the eNB can configure one repetitionnumber and the UE determines the repetition number for dedicated channelbased on uplink control information content. For example, the repetitionnumber of the dedicated physical channel configured by the eNB isassumed to be N_(rep). When a scheduling request is transmitted, the UEtransmits the dedicated physical channel, the repetition number of whichis N_(rep) (or ┌M·N_(rep)┐). When a scheduling request is nottransmitted, the repetition number is ┌M·N_(rep)┐ (or N_(rep)), wherein┌x┐ denotes the smallest integer greater than or equal to x, and M is apositive number with fixed or configured value by eNB.

The dedicated physical can also be an NPUSCH Format 2 introducing morecode words (for example, more than two code words), the code words areused for indicating a scheduling request and an HARQ-ACK information.For example, besides the current all-zeros sequence that the indicationHARQ-ACK bit being 0 and the current all-ones sequence that theindication HARQ-ACK bit being 1, more orthogonal code word sequences areused for indicating an additional 1 bit of scheduling requestinformation. The codeword sequences are generated to ensureorthogonality of modulated codeword sequences (e.g., Walsh code), toensure the semi-orthogonality of the aggregated modulated codewordsequences and demodulation reference signal sequences, to adoptsemi-orthogonal complex sequences (e.g., m sequence), or to adoptorthogonal complex sequences (e.g., DFT sequence). Table 5 shows anexample of a code word format table of uplink control information, whichis scheduling request bit O^(SR) and HARQ-ACK bit O^(ACK) as follows:

TABLE 5 <O^(SR), O^(ACK)> Code words <b0, b1, b2, . . . , b15> 00 <0, 0,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0> 01 <1, 1, 1, 1, 1, 1, 1, 1, 1,1, 1, 1, 1, 1, 1, 1> 10 <0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1>11 <1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0>

When the dedicated physical channel transmits piggybacked schedulingrequest bit with an ACK/NACK information bit, the used subcarrier andthe transmission start time are respectively the subcarrier and thetransmission start time used for the NPUSCH Format 2 indicated in thedownlink grant. The repetition number can be configured by RRCsignaling, e.g., use the repetition number for the NPUSCH Format 2indicated in an RRCConnectionReestablishment-NB information. Otherwise,the UE can determine the repetition number for a dedicated channel basedon uplink control information content. For example, the repetitionnumber of the dedicated physical channel configured by the eNB isassumed to be N_(rep). When a scheduling request is transmitted, the UEtransmits the dedicated physical channel, the repetition number of whichis N_(rep) (or ┌M·N_(rep)┐). When a scheduling request is nottransmitted, the repetition number is ┌M·N_(rep)┐ (or N_(rep)) , wherein┌x┐ denotes the smallest integer greater than or equal to x, and M is apositive number with fixed or configured value by eNB.

A UE decides whether the transmitting a scheduling request is completedaccording to a second decision rule, and considers the transmitting ascheduling request to be completed when the UE receives an uplink grantwithin a RAR time window, and the scheduling request is not attempted tobe transmitted. Otherwise, the scheduling request is continuallyattempted to be transmitted. The physical channel used for reattemptingto transmit the scheduling request can be different with the physicalchannel used for initially transmitting the scheduling request. Forexample, the physical channel used for reattempting to transmit thescheduling request is an NPUSCH Format 2 and the physical channel usedfor initially transmitting the scheduling request is the dedicatedphysical channel described by this method. And the time-and-frequencyresource configuration mode used for reattempting to transmit thescheduling request can be same or different with the time-and-frequencyresource configuration mode in the initial transmission, and theavailable configuration mode can be the configuration mode described byWay 1 and Way 2.

Embodiment 4

In this embodiment, a method for reporting scheduling request in an NBIoT system is described, which is used for reporting scheduling requeston a semi-static-configured time-and-frequency physical resource.

The mode, of acquiring the configured frequency physical resource andtime physical resource by a UE, can multiplex the NPUCCH resourcetransmitted by a LTE scheduling request and the mode of transmissioninstance. The dedicated physical channel for transmitting a schedulingrequest, as described above with reference to Embodiment 2, canmultiplex a current NPUSCH Format 2, or can use the dedicated physicalchannel as described in Way 2 of Embodiment 3,

After acquiring, by a UE, the time-and-frequency resource used fortransmitting a scheduling request, when the UE transmits a schedulingrequest at this time, the UE is required to determine thetime-and-frequency resource for transmitting a scheduling request orterminate the transmitting a scheduling request.

The UE can determine whether to reattempt to report a scheduling requestaccording to a second decision rule. The decision process can be that,for example, deciding whether to report a scheduling request and, ifnot, continually deciding, at this time, whether there is a conflictbetween the available time-and-frequency resource used for transmittinga scheduling request by a UE and the time-and-frequency resource usedfor transmitting the uplink physical channel by the UE If there is aconflict, the reporting of a scheduling request can be abandoned, or atime frequency is updated, which is used when reporting a schedulingrequest according to a updating rule. The updating rule comprisesdeferring to report a scheduling request or using an adjacent subcarrierof a subcarrier used by an NPUSCH Format 2.

For example, when the UE determines there is a conflict between theavailable time-and-frequency resource used for transmitting a schedulingrequest by a UE and the time-and-frequency resource used fortransmitting the uplink physical channel by the UE, the UE can abandonreporting a scheduling request, or select a new resource to transmit ascheduling request or an uplink physical channel according to a certainrule (that is, an updating rule).

For example, as for an uplink shared channel format 1 or uplink sharedchannel format 2, when there is a conflict between thetime-and-frequency resource used for transmitting by an eNB and theresource of a scheduling request, the UE can defer to transmit ascheduling request (or defer to transmit an uplink shared channel format1/uplink shared channel format 2), and transmit on the firsttime-and-frequency resource being capable of transmitting a schedulingrequest after the transmitting the uplink shared channel format 1/uplinkshared channel format 2 ends (or, starting to transmit the uplink sharedchannel format 1/uplink shared channel format 2 after a fixed time fromthe scheduling request transmission end). In another example, as for anuplink shared channel format 1 and uplink shared channel format 2, whenthere is a conflict between the scheduled time-and-frequency resourceand the resource of the scheduling request, a scheduling request can betransmitted, according to a certain rule, on a frequency resourceconfigured not by the two formats, and the rule can be a neighborsubcarrier of a subcarrier used when an uplink shared channel format 1and uplink shared channel format 2 are used. Similarly, an uplink sharedchannel format 1 and uplink shared channel format 2 can be enabled touse the frequency resource not configured by the two formats to performtransmission. As for a downlink channel, for example, a physicaldownlink control channel and a physical downlink shared channel, if atthis moment, the UE is required to report a scheduling request, but thereceiving of an uplink channel is being performed, the UE terminates toreport a scheduling request or defers to transmit a scheduling request,until the UE can perform uplink transmission. As for an uplink randomaccess channel, when there is a resource configuration conflict, the UEdoes not transmit a scheduling request on a random access channelresource configured by a system, it can be deferred to transmit thescheduling request or select a new subcarrier to transmit a schedulingrequest according to a certain rule, and the rule is same with the abovedescribed. If at this moment, the UE is during an uplink gap period, theUE can abandon the transmitting of a scheduling request.

Embodiment 5

In this embodiment, a method for configuring a time-and-frequencyresource is described, which can be used for transmitting a physicalchannel for a scheduling request, the physical channel at leastcomprises an NPRACH or NPUSCH Format 2.

In operation 1, an eNB can configure a reserved time-and-frequency blockused for transmitting a scheduling request physical channel. Thespecific mode can be that, the UE configures part of all the initialsubcarriers of repeated levels of an NPRACH to be used for an NPRACH(parameters nprach-NumCBRA-StartSubcarriers can pass through, and it isa prior technology) used for a contention-based random access, and theother reserved initial subcarriers can be used for transmitting anNPRACH which is activated by an NPDCCH order, and/or used for a physicalchannel for reporting scheduling request. The physical channel at leastcomprises one of the following: NPUSCH Format 2, a non-frequency hoppingtransmission NPRACH (that is, a plurality of symbol groups of the NPRACHand multi-repetitions of the NPRACH are all transmitted on a samesubcarrier), and a frequency hopping transmission NPRACH. When the partof the reserved subcarriers are used for transmitting the physicalchannel for reporting scheduling request, the number of the reservedinitial subcarriers is required to be greater than or equal to multiplesof 12.The eNB can select 12 or multiples of 12 neighbor reserved initialsubcarriers to be used for transmitting the physical channel forreporting scheduling request, and other parts of the reserved initialsubcarriers for transmitting an NPRACH which is activated by an NPDCCHorder.

FIG. 11 is a schematic diagram of the configuring an NPRACH resource byan eNB according to an embodiment of the disclosure.

In operation 2, the UE can acquire the UE-specific time-and-frequencyresource allocation information of the physical channel, which isconfigured by the eNB, for transmitting a scheduling request. The UE isfirst required to acquire the repeated level of NPRACH to which thereserved resource, used by the physical channel for transmitting ascheduling request, belongs. The selection of the repeated level of theNPRACH can multiplex the repeated level of the NPRACH selected duringthe initial access of the UE, or can be configured by the eNB through asignaling. In addition, the UE needs to acquire a start time, atransmission time and a subcarrier index (equivalent to that thesubcarrier index is an initial subcarrier index when the physicalchannel for a scheduling request is an NPRACH Format 0 or NPRACH Format1). When there are more than one subcarrier interval configuration inthe physical channel for transmitting a scheduling request (for example,the physical channel for transmitting a scheduling request is an NPUSCHFormat 2), the eNB is required to configure a subcarrier interval foreach UE, wherein the subcarrier interval can multiplex the uplinksubcarrier interval configuration obtained by the UE during a randomaccess, or is further configured by the eNB. For example, for thephysical channel for transmitting a scheduling request being an NPUSCHFormat 2.

FIG. 12 is a schematic diagram of acquiring, by a UE, configurationparameters to obtain time-and-frequency resources of a physical channeltransmitting a scheduling request according to an embodiment of thedisclosure.

Referring to FIG. 12 , a schematic diagram illustrates acquiring, by aUE, the configuration parameters to obtain time-and-frequency resourcesof a physical channel transmitting a scheduling request according to anembodiment of the disclosure. The start time can be an arbitrarysubframe (or time slot) in a duration time of a reserved resource, asshown in FIG. 12 . For the transmission time, the content of which canbe the repeated number of the physical channel, or the number of theNPRACH symbol groups (that is, it is allowed that the UE transmits oneor more symbol groups to be used for reporting scheduling request). Whenthere is more than one subcarrier interval configuration in the physicalchannel for transmitting a scheduling request, the initial subcarrierindex can be defined according to a subcarrier interval of 3.75 kHz. Forexample, twelve initial subcarriers (3.75 kHz) are assumed to bereserved in the repeated level of the NPRACH, thus when the subcarrierinterval configured by a UE is 15 kHz, and when the subcarrier index is0, the frequency location of the 1st to the 4th subcarriers of 3.75 kHzis correspondingly used. When the subcarrier index is 1, the frequencylocation of the 2nd to the 5th subcarriers of 3.75 kHz iscorrespondingly used. In another example, the frequency location of thesubcarriers can be defined according to the subcarrier intervalconfigured actually by the UE. For example, twelve initial subcarriers(3.75 kHz) are assumed to be reserved in the repeated level of theNPRACH, thus when the subcarrier interval configured by a UE is 15 kHz,when the subcarrier index is 0, the frequency location of the 1st to the4th subcarriers of 3.75 kHz is correspondingly used. When the subcarrierindex is 1, the frequency location of the 5th to the 8th subcarriers of3.75 kHz is correspondingly used, and so on for the frequency locationsof other index values.

FIG. 9 is a schematic diagram of a device for reporting schedulingrequest in an NB IoT system according to an embodiment of thedisclosure.

Referring to FIG. 9 , according to an aspect of the disclosure, a devicefor reporting scheduling request in NB IoT systems is provided, whichcomprises an acquisition module 101 and a transmitting module 102. Theacquisition module 101 is configured to acquire a dedicated physicalresource of a physical channel used for reporting scheduling request,wherein the dedicated physical resource comprises a plurality ofperiodical physical resources. The transmitting module 102 is configuredto transmit, when a scheduling request is triggered, the NPRACH on theavailable dedicated physical resource, so as to report the schedulingrequest. The device is equipped with one or more applications, whereinthe one or more applications are stored in a storage, and are configuredto be executed by one or more processors, and the one or moreapplications are configured to be used for: performing the method forreporting scheduling request in NB IoT systems according to anyembodiment as shown in FIG. 2 .

FIG. 10 is a schematic diagram of a device for reporting a schedulingrequest in an NB IoT system according to an embodiment of thedisclosure.

Referring to FIG. 10 , according to another aspect of the disclosure, adevice for reporting scheduling request in NB IoT systems is provided,which comprises an acquisition module 201 and a reporting module 202.The acquisition module 201 is configured to acquire thetime-and-frequency resources of dedicated physical channel for reportingscheduling request. The reporting module 202 configured to transmit thededicated physical channel on the time-and-frequency resources, so as toreport the scheduling request, when a scheduling request is triggered.The dedicated physical channel is a NPUSCH Format 2, or an NPUSCH Format2 with a high-order modulation mode, or an NPUSCH Format 2 using morethan two code words. The device is equipped with one or moreapplications, wherein the one or more applications are stored in astorage, and are configured to be executed by one or more processors,and the one or more applications are configured to be used for:performing the method for reporting scheduling request in NB IoT systemsaccording to any embodiment as shown in FIG. 3 .

FIG. 13 is a schematic diagram of one example of NPRACH cover scramblingused in large cell radius according to an embodiment of the disclosure.

Referring to FIG. 13 , according to the method and device for reportingscheduling request in NB IoT systems provided in the above embodiment,efficiency of transmitting a scheduling request information is improved,either a current unlink physical channel is multiplexed to transmit on aUE-specific resource to indicate a scheduling request, or a dedicatedphysical channel is designed to transmit a scheduling requestinformation.

According to one aspect of the disclosure, an eNB is provided, which isconfigured to transmit a dedicated physical resource to a UE, so thatthe UE performs the method for reporting scheduling request in NB IoTsystems according to any embodiment of the above, and in this method,the UE is required to acquire the dedicated physical resource.

According to another aspect of the disclosure, an eNB is provided, whichis configured to transmit a configuration information to a UE, so thatthe UE performs the method for reporting scheduling request in NB IoTsystems according to any embodiment of the above, and in this method,the UE is required to acquire the time-and-frequency resourceinformation.

It should be understood by those skilled in the art that the disclosureinvolves devices for carrying out one or more of operations as describedin the disclosure. Those devices can be specially designed andmanufactured as intended, or can comprise well known devices in ageneral-purpose computer. These devices have computer programs storedtherein, which are selectively activated or reconfigured. Such computerprograms can be stored in device (such as computer) readable media or inany type of media suitable for storing electronic instructions andrespectively coupled to a bus, the computer readable media include butare not limited to any type of disks (including floppy disks, harddisks, optical disks, a read only memory (ROM), random access memory(RAM), compact disc (CD)-ROM and magneto optical disks), random accessmemory (RAM), erasable programmable ROM (EPROM), electrically erasableprogrammable ROM (EEPROM), flash memories, magnetic cards or opticalline cards. In other words, the readable media comprise any mediastoring or transmitting information in a device (for example, computer)readable form.

It can be understood for those skilled in the art that each block of thestructure charts and/or block diagrams and/or flowchart illustrations,and combinations of blocks in the structure charts and/or block diagramsand/or flowchart illustrations, can be implemented by computer programinstructions. It can be understood for those skilled in the art that thecomputer program instructions may also be supplied to a general purposecomputer, a special purpose computer or other processor capable ofprogramming data processing method for implementation, such that schemesspecified in one or more block of the structure charts and/or blockdiagrams and/or flowchart illustrations are implemented by a computer orother processor capable of programming data processing method.

It can be understood for those skilled in the art that variousoperations, methods, operations in a flow, measures and schemes that hasbeen discussed in the disclosure may be alternated, changed, combined ordeleted. In addition, those with various operations, methods, operationsin a flow, measures and schemes that has been discussed in thedisclosure may further be alternated, changed, rearranged,disintegrated, combined or deleted. In addition, in the prior art, thosewith various operations, methods, operations in a flow, measures andschemes that discussed by the disclosure may further be alternated,changed, rearranged, disintegrated, combined or deleted.

While the disclosure has been shown and described with reference tovarious embodiments thereof, it will be understood by those skilled inthe art that various changes in form and details may be made thereinwithout departing from the spirt and scope of the disclosure as definedby the appended claims and their equivalents.

What is claimed is:
 1. A method for reporting a scheduling request, themethod comprising: generating modulation symbols a_(i)b^(i), based onmultiplication of hybrid automatic repeat request (HARQ)-acknowledgement(ACK) feedback a_(i) with a codeword b_(i) for the scheduling request;and transmitting the modulation symbols on a narrowband physical uplinkshared channel (NPUSCH), wherein in case that the scheduling request isto be transmitted using NPUSCH format 2, the codeword for the schedulingrequest is b_(i),i=0,1, . . . ,
 15. 2. The method of claim 1, furthercomprising generating the HARQ-ACK feedback a_(i) for the NPUSCH.
 3. Themethod of claim 1, wherein the method for reporting the schedulingrequest is provided in a narrowband IoT) system.
 4. A method forreceiving a scheduling request, the method comprising: receivingmodulation symbols on a narrowband physical uplink shared channel(NPUSCH), and identifying hybrid automatic repeat request(HARQ)-acknowledgement (ACK) feedback a and a codeword b, for thescheduling request, from the received modulation symbols, wherein themodulation symbols, a_(i)b_(i), are generated based on multiplication ofthe HARQ-ACK feedback a_(i) with the codeword b_(i) for the schedulingrequest, in case that the scheduling request is to be transmitted usingNPUSCH format 2, the codeword for the scheduling request is b_(i),i=0,1,. . . ,
 15. 5. The method of claim 4, wherein a method for receiving thescheduling request is provided in a narrowband IoT system.
 6. A userequipment (UE) for reporting a scheduling request, the UE comprising: atransceiver; and a processor coupled with the transceiver and configuredto: generate modulation symbols a_(i)b_(i), based on multiplication ofhybrid automatic repeat request (HARQ) acknowledgement (ACK) feedbackca_(i) with a codeword b _(i) for the scheduling request, and transmitthe modulation symbols on a narrowband physical uplink shared channel(NPUSCH), wherein in case that the scheduling request is to betransmitted using NPUSCH format 2, the codeword for the schedulingrequest is b_(i),i=0,1, . . . ,
 15. 7. The UE of claim 6, wherein theprocessor is further configured to generate the HARQ-ACK feedback a_(i)for the NPUSCH.
 8. The UE of claim 6, wherein the UE for reporting thescheduling request is included in a narrowband IoT system.
 9. An evolvednode B (eNB) for receiving a scheduling request, the eNB comprising: atransceiver; and a processor coupled with the transceiver and configuredto: receive modulation symbols on a narrowband physical uplink sharedchannel (NPUSCH), and identify hybrid automatic repeat request(HARQ)-acknowledgement (ACK) feedback a_(i) and a codeword b_(i) for thescheduling request, from the received modulation symbols, wherein themodulation symbols, a_(i)b_(i), are generated based on multiplication ofthe HARQ-ACK feedback a_(i) with the codeword b_(i) for the schedulingrequest, in case that the scheduling request is to be transmitted usingNPUSCH format 2, the codeword for the scheduling request is b_(i),i=0,1,. . . ,
 15. 10. The eNB of claim 9, wherein the eNB for receiving thescheduling request is included in a narrowband IoT system.